Quick-detachable dust cap for pneumatic tires



W. E. WILLIAMS.

Q UICK DETACHABLE DUST CAP FOR PNEUMATIC TIRES.

I APPLICATION FILED'JULY 6.1920. 1,421,642. Patented July 4, 1922.

l@WILLIAM IELIEtAS'JIITS WILLIAMS, 0F CHICAGO, ILLINOIS.

QUICK-DETACHABLE 'DUST CAP FOR PNEMATIC TIR-IES.

' mareas.

To allr whom t may concern.'

Be it known that I, WILLIAM ERAS'I'US WILLIAMS, a citizen of the UnitedStates, a resident of Chicago, in the county of Cook and State ofIllinois, have invented a new and useful Improvement in Quick-DetachableDust Caps for Pneumatic Tires, ofl which the following is aspecification.

My invention relates to dust caps which enclose and protect valve stems.

The object of my invention is to provide a very cheaply constructed,quick detachable cap that may be applied to and removed from the valvestem in the most expeditious manner and at the same time be adjustedalong the valve stem and be practically secure against accidentaldisplacement.

Reference will be had to the accompanying drawings in which Figure 1 isa sectional elevation of a part of a rim of a wheel with my valve cap inplace., f

Figure 2 is an enlarged central sectional view similar to that of Figure1.

Figure 3 is a detail sectional view of the valve cap itself on the samescale as that of Figure 2.. i

'Figure 4 is a transverse sectional View when the cap is secured inplace.

Figure 5 is a view similar to that of Figure 4 showing the position ofthe parte when my cap is being pushed on to the-valve stem.

In the drawing l indicates the felloe and rim of a wheel which may beof-any desired type and no details of this are given. 2 indicates asection through the rubber4 tube to which the valve stem '-3 is securedin any suitable way. (Dn the end of this stem is the ordinary cap 4-generally used with valve stems. The standard ordinary valve stem hastwo iattened surfaces indicated by 5 and these surfaces are on the sidesin Figure 2'.

The valve stem 3 is threaded its entirel length but as above stated itis attened so that the threads are wanting on the sides 5 and appearonly on. the surfaces indicated by 6' in Figures 4 and 5.

My valve cap is indicated by 7 and is shapedin cross section as shown inFigures 4 and 5 wherein there are swells or recessed pockets 8 on twosides and in these recesses there is mounted peculiarly shaped spring 9which is secured lnto the head of the valve cap by a rivet 10 or byother suitable means.'

stem but there is sufficient elasticity'in the' body of the spring topermit the valve stem ,Specification of Letters Patent.

`threads 12 mutilated so as to 4to be turned `90 degrees from theposition Aof Figure 4 to that of the position -of Figure 5 wherein thespring contact surfaces 11 press on the thread surfaces 6 of the'stem.In this position the valve cap 7 may be pushed on or removed from force.

In the lower end of my cap I provide provide only narrow bearing threadortions as indicated in Figures 4 and 5. In IFigure 4 my threads l2 arein engagement with the threads 6 of the valve stem but in Figure 5 thethreads 12 are opposite the fiat surfaces 5 of the valve stem itself;

In Figure 4 the bearing surfaces 1l em- Y brace the flat surfaces 5- othe stem and act as a nut lock to prevent the turning of thecap on thevalve stem andthe threads 12 are 1n engagement with the threads 6 andthus the cap is held securely in place.

When it is desired to remove the cap 7 it is revolved 90 degrees,disengaging the threads 12 and bringing the Contact surfaces 11 on tothe thread 6 and then the valve cap may be v pulled od'. On replacingthe4 dust cap 7 it is tion thereof and normally projecting within thecircleof the threaded portion of a valve stem upon which it may beplaced.

2. The combination with avalve stem member having external threads cutaway the valve stem by slight Patented July 4, i922. y -lli'iplicationled July 6, 1920. Serial No. 394,153.

along a longitudinal line, of a stem-enclosirg dust capmember havingmutilated threa adapted to engage and disengage the stem threads duringrelative rota-tion, and spring devices between said members constantlypressing them at various points in their length and resisting whilepermitting their relative rotation.

3. In a device of the class described, a tubular dust cap having a Ushaped spring se= cured within the cap and adapted to rese on two sidesof the valve stem over Whic the cap is placed.

4. In a device of the class described, a-dust cap composed of a tubularmember adapted to be applied over the s indle of an air valve and saidtubular mem er having threaded portions on the inside and opposite eachSigned at Chicago, in the county of Cook other and for only shortlsections around the and State of Illinois, this twenty-ninth daycircumference; in. combination with recesses of June. 1920.4

on the inside of the cap located at 90 degrees Wil-UAM ERSTUS WILLIAMS-5 from the said thread portions of the cap and Witnesses:

with sprin contact devices located Within F. ZoBEL,

the recesse portions. i h B. J. BERNHARD.

